Otitis externa

Also called Swimmer's ear, Outer ear infection

Infection of the ear canal. Painful, usually straightforward, and in diabetes it can become a serious skull-base infection.

What it is

Otitis externa is inflammation or infection of the outer ear canal. It is common, particularly after swimming, in hot humid weather, and in people who use cotton buds or wear hearing aids or earplugs.

The canal has a protective wax and acid layer. Anything that removes it, water, cotton buds, over-cleaning, lets bacteria or fungus take hold.

It is usually treated easily with drops. The reason it earns an entry is a rare but serious complication: necrotising otitis externa, where the infection spreads into the bone at the base of the skull. It occurs almost exclusively in older people with diabetes or immunosuppression, it causes severe unrelenting pain, and it can be fatal.

Signs you might notice

Ear pain, often severe, and worse when the outer ear is pulled or pressed.

Itching in the canal, which often comes first.

Discharge, and a blocked or muffled ear.

Redness and swelling of the canal.

Warning signs of necrotising otitis externa: severe pain out of proportion, particularly at night, in an older person with diabetes; pain persisting despite treatment; granulation tissue in the canal; facial weakness.

Facial weakness with an ear infection is an emergency.

How it can affect day-to-day life

Hearing aid users are affected disproportionately, and an infection means the aid cannot be worn, which causes withdrawal and apparent confusion in older people. See deafness and hearing loss.

Recurrent otitis externa is usually a habit problem: cotton buds, over-cleaning, or water retention after swimming.

Drops fail most often because the canal is too swollen or full of debris for them to reach; microsuction by an ENT service is what resolves those cases.

Supporting someone well

Keep the ear dry. Cotton wool with petroleum jelly while showering, and no swimming until it has settled.

Never use cotton buds, in an infection or otherwise.

Use the drops properly: lie with the affected ear up, instil the drops, and stay there for several minutes. Most people sit up immediately and the drops run straight out.

Take the pain seriously; otitis externa hurts a great deal and pain relief is often inadequate.

For hearing aid users, clean the mould and take a break from the aid during infection, but get it treated quickly so they are not without it for long.

Escalate severe or persistent pain in an older person with diabetes urgently.

Where to get help

A pharmacist can advise; a GP for treatment with drops.

Ask for ENT referral for persistent infection, a swollen canal needing microsuction, or recurrent episodes.

Severe pain in a person with diabetes, or any facial weakness, needs urgent assessment.